**Alexey Vereschaka 1,\*, Sergey Grigoriev 2, Anatoli Chigarev 3, Filipp Milovich 4, Nikolay Sitnikov 5, Nikolay Andreev 4, Gaik Oganian <sup>2</sup> and Jury Bublikov <sup>1</sup>**


Received: 28 August 2020; Accepted: 27 September 2020; Published: 28 September 2020

**Abstract:** The study proposes a model for the deposition of coatings, which takes into account the stochastic nature of the deposition process and is built considering the influence of the parallel convection and diffusion processes. The investigation has found that the dispersion of the motion direction of deposited particles in front of a substrate increases, which indicates a growth of the randomness in the trajectories of the particles being deposited. The obtained formulas indicate the fractal nature of the deposition process. During the formation of the multilayer coating structure, mismatched fractal structures of the layers overlap each other and thus the clustering effect is largely leveled out. The value of the nanolayer λ period has a significant influence on the fractal structure of the coating and the formation of feather-like hierarchical structures in it.

**Keywords:** hierarchical structure; multilayer PVD coating; stochastic process; convection and diffusion
